Zero-gangue-discharge short-wall face pillar-free mining method

ABSTRACT

The present invention discloses a zero-gangue-discharge short-wall face pillar-free mining method, which is applicable to zero-gangue-discharge disposal in the mining operation in a mine shaft. A short-wall face is arranged in a selected area near a mine shaft according to the actual conditions of the mine shaft, the short-wall face is mined in a fully mining and fully back-filling mode, the gangues produced at other mining faces of the mine shaft are filled into the short-wall face, the short-wall face is supported with anchor rods along the edge of the filling face and the solid coal side to form an entry, and the entry is utilized to mine an adjacent working face. The method in the present invention mainly displaces the coal mass with gangues and thereby maximizes the utilization of the resources; in addition, the method can fully control the roof and realize mining without damage to the rock formation. Therefore, the method is of great value for wide application.

TECHNICAL FIELD

The present invention relates to a zero-gangue-discharge short-wall facepillar-free mining method, which is especially applicable tozero-gangue-discharge disposal in the mining operation in a mine shaft.

BACKGROUND ART

Hundreds of million tons of gangues are produced in the coal mines ineach year in China. However, at present, those gangues in the coal minesare mainly disposed by open stacking. Consequently, a great deal of landis occupied, and original landform and vegetation are buried under thegangues or damaged; in addition, spontaneous ignition may occur easilyowing to open stacking, and may produce toxic substances that may causesevere harms to the living environment of human kind and the ecologicalenvironment in the mine field.

Many ways for gangue disposal have been worked out in China, but, inmost of the ways, gangues are discharged first from coal mines beforethey are utilized. Consequently, though a part of the gangues aredisposed, a great deal of dust is produced in the process of ganguedischarge and disposal, resulting in secondary pollution to theenvironment. Presently, there is an urgent need for a coal mining methodthat can realize zero discharge of downhole gangue.

CONTENTS OF THE INVENTION

Technical Problem: the purpose of the present invention is to overcomethe drawbacks in the prior art, to provide a zero-gangue-dischargeshort-wall face pillar-free mining method, which is simple but canattain a good effect.

Technical Scheme: a zero-gangue-discharge short-wall face pillar-freemining method, comprising the following steps:

a. arranging a short-wall face in an area near the shaft station of amine shaft according to the actual conditions of the mine shaft, themining starting position of the short-wall face is 500 m˜1,000 m awayfrom the shaft station and the short-wall face is mined in a directionaway from the shaft station;

b. transporting all gangues produced at other mining faces of the mineshaft to the short-wall face, mining the short-wall face in a fullymining and fully back-filling mode, and filling the short-wall face withthe gangues; at the same time, supporting the roof and side walls of aroadway in the milling process with anchor rods, including supportingthe roadway along the edge of a filling face and the solid coal side ofthe short-wall face; forming an entry at the outer side of theshort-wall face after the supporting, and excavating a roadway at theouter side of a short-wall face adjacent to the current short-wall faceat the same time;

c. excavating an open-off cut from the roadway to the current short-wallface after the roadway is excavated; utilizing the entry and theadjacent excavated roadway to form a backfill-mining working face at anadjacent short-wall face, continuing the mining in a fully mining andfully back-filling mode and filling the adjacent short-wall face withgangues; at the same time, transferring the excavating equipment toexcavate adjacent roadway and open-off cut of a next short-wall face toprepare for the follow-up mining of the next short-wall face;

e. repeating the steps b and c and thereby realizing continuous miningof the short-wall face, with the gangues disposed in the mine shaft,till all gangues produced in the downhole operation are disposed in themine shaft; thus, zero gangue discharge on the ground surface isrealized.

The short-wall face is used to dispose gangues underground, and theshort-wall face is in 30˜50 m width, in height equal to the height ofthe coal seam, and in 1,000 m˜3,000 m length. The entry is in 3˜6 mwidth. The short-wall face is mined in a mining sequence of alternatingforward mining and backward mining, and the roadway is excavated alwaysby forward excavation.

Beneficial effects: with the above-mentioned technical scheme, themethod provided in the present invention has the following advantagesover the prior art:

(1) All solid wastes such as all gangues or the like produced in thecoal mining process are directly disposed underground by back-filling,and don't have to be discharged to the ground surface anymore.Therefore, a goal of zero gangue discharge is attained, environmentalpollution resulted from gangue discharge is avoided, and the costincurred by gangue disposal on the ground surface is greatly reduced aswell.

(2) Small-size coal cutters and about 10 filing hydraulic supports areonly required for short-wall face mining. Therefore, high productioncost in the mine shaft is avoided, and the problems of low recoveryefficiency and delay of normal production incurred by the currentfilling techniques are solved.

(3) Since an entry is reserved after the backfill mining of theshort-wall face, the roadway excavation work is reduced, and the cost ofroadway excavation is reduced.

(4) By displacing the coal mass with gangues and canceling pillars, theutilization of resources is maximized; in addition, by utilizing a fullymining and fully back-filling mode for the short-wall face, the roof canbe controlled fully, and mining without damage to the rock formation isrealized. Therefore, it is a method of a great value for wideapplication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows forward mining of a short-wall face in thezero-gangue-discharge short-wall face pillar-free mining methodaccording to the present invention;

FIG. 2 shows backward mining of the short-wall face in thezero-gangue-discharge short-wall face pillar-free mining methodaccording to the present invention.

In the figures: 1—short-wall face; 2—entry; 3—roadway; 4—open-off cut;5—adjacent short-wall face; 6—adjacent roadway.

EMBODIMENTS

Hereunder the present invention will be further detailed in anembodiment with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the zero-gangue-discharge short-wall facepillar-free mining method according to the present invention comprisesthe following steps:

a. arranging a short-wall face 1 in an area near the shaft station of amine shaft according to the actual conditions of the mine shaft, theshort-wall face 1 is used to store gangues underground, and is in 30˜50m width, in height equal to the height of the coal seam, and in 1,000m˜3,000 m length; the mining starting position of the short-wall face 1is 500 m˜1,000 m away from the shaft station, and the short-wall face 1is mined in a direction away from the shaft station, in a miningsequence of alternating forward mining and backward mining; whileexcavating the short-wall face 1 always by forward excavation;

b. transporting all gangues produced at other mining faces of the mineshaft to the short-wall face 1, mining the short-wall face 1 in a fullymining and fully back-filling mode, and filling the short-wall face 1with the gangues; at the same time, supporting the roof and side wallsof the roadway in the milling process with anchor rods, includingsupporting the roadway along the edge of a filling face and the solidcoal side of the short-wall face 1; forming an entry 2 in 3˜6 m width atthe outer side of the short-wall face 1 after the supporting, andexcavating a roadway 3 at the outer side of a short-wall face 5 adjacentto the current short-wall face 1 at the same time;

c. excavating a open-off cut 4 from the roadway 3 to the currentshort-wall face 1 after the roadway 3 is excavated; utilizing the entry2 and the adjacent excavated roadway 3 to form a backfill-mining workingface at an adjacent short-wall face 5, continuing the mining in a fullymining and fully back-filling mode and filling the adjacent short-wallface 5 with gangues; at the same time, transferring the excavatingequipment to excavate adjacent roadway 6 and open-off cut 4 of a nextshort-wall face to prepare for the follow-up mining of the nextshort-wall face;

e. repeating the steps b and c and thereby realizing continuous miningof the short-wall face 1, with the gangues disposed in the mine shaft,till all gangues produced in the downhole operation are disposed in themine shaft; thus, zero downhole gangue discharge is realized.

1. A zero-gangue-discharge short-wall face pillar-free mining method,comprising the following steps: a) arranging a short-wall face in anarea near a shaft station of a mine shaft according to actual conditionsof the mine shaft, a mining starting position of the short-wall face is500 m˜1,000 m away from the shaft station, and the short-wall face ismined in a direction away from the shaft station; b) transporting allgangues produced at other mining faces of the mine shaft to theshort-wall face, mining the short-wall face in a fully mining and fullyback-filling mode, and filling the short-wall face with the gangues; atthe same time, supporting a roof and side walls of a roadway in themilling process with anchor rods, including supporting the roadway alongan edge of a filling face and a solid coal side of the short-wall face;forming an entry at an outer side of the short-wall face aftersupporting, and excavating a roadway at an outer side of a short-wallface adjacent to the current short-wall face at the same time; c)excavating an open-off cut from the roadway to the current short-wallface after the roadway is excavated; utilizing the entry and theadjacent excavated roadway to form a backfill-mining working face at anadjacent short-wall face, continuing the mining in a fully mining andfully back-filling mode and filling the adjacent short-wall face withgangues; at the same time, transferring excavating equipment to excavateadjacent roadway and open-off cut of a next short-wall face to preparefor the follow-up mining of the next short-wall face; d) repeating thesteps b and c and thereby realizing continuous mining of the short-wallface, with the gangues disposed in the mine shaft, until all ganguesproduced in the downhole operation are disposed in the mine shaft; thus,zero downhole gangue discharge is realized.
 2. The zero-gangue-dischargeshort-wall face pillar-free mining method according to claim 1, wherein,the short-wall face is used to dispose gangues underground, and theshort-wall face is 30˜50 m in width, in height equal to a height of thecoal seam, and 1,000 m˜3,000 m in length.
 3. The zero-gangue-dischargeshort-wall face pillar-free mining method according to claim 1, wherein,the entry is 3˜6 m in width.
 4. The zero-gangue-discharge short-wallface pillar-free mining method according to claim 1, wherein, theshort-wall face is mined in a mining sequence of alternating forwardmining and backward mining, and the roadway is excavated always byforward excavation.